Clinical characteristics and genetic analysis of childhood acute lymphoblastic leukemia with hemophagocytic lymphohistiocytosis: a Japanese retrospective study by the Kyushu–Yamaguchi Children’s Cancer Study Group

This present study sought to analyze acute lymphoblastic leukemia (ALL) patients with hemophagocytic lymphohistiocytosis (HLH) registered in Kyushu–Yamaguchi Children’s Cancer Study Group studies conducted between 1996 and 2007. Four of 357 patients, including two of 318 patients with B cell precursor acute lymphoblastic leukemia (BCP-ALL) and two of 39 of those with T cell acute lymphoblastic leukemia (T-ALL), were identified. HLH was observed more frequently in the T-ALL patients than in the BCP-ALL patients (P = 0.061). The mean age of 13.0 years at the diagnosis of leukemia in the HLH + ALL group was significantly higher than the 6.05 years observed in the remaining ALL groups (P = 0.001). A female predisposition was noted, as all four patients were female (P = 0.043). In two of four patients, the leukemic cells exhibited deletions on the long arm of chromosome 6 (P = 0.003). Three patients suffered from HLH during maintenance therapy. Parvovirus B19 infection and cytomegalovirus reactivation were identified as causes of HLH in one and two patients, respectively. All four patients are currently in complete remission, although one developed relapse of leukemia after receiving maintenance therapy. Based on the genetic analyses, non-synonymous single nucleotide polymorphisms (SNPs) in UNC13D, syntaxin 11, and STXBP2 were identified in all patients. Clinicians should therefore be aware of the risk of HLH during maintenance therapy, especially in older T-ALL patients with SNPs in familial HLH causative genes.     

Terreic acid, a quinone epoxide inhibitor of Bruton's tyrosine kinase

Bruton's tyrosine kinase (Btk) plays pivotal roles in mast cell activation as well as in B cell development. Btk mutations lead to severe impairments in proinflammatory cytokine production induced by cross-linking of high-affinity IgE receptor on mast cells. By using an in vitro assay to measure the activity that blocks the interaction between protein kinase C and the pleckstrin homology domain of Btk, terreic acid (TA) was identified and characterized in this study. This quinone epoxide specifically inhibited the enzymatic activity of Btk in mast cells and cell-free assays. TA faithfully recapitulated the phenotypic defects of btk mutant mast cells in high-affinity IgE receptor-stimulated wild-type mast cells without affecting the enzymatic activities and expressions of many other signaling molecules, including those of protein kinase C. Therefore, this study confirmed the important roles of Btk in mast cell functions and showed the usefulness of TA in probing into the functions of Btk in mast cells and other immune cell systems. Another insight obtained from this study is that the screening method used to identify TA is a useful approach to finding more efficacious Btk inhibitors.     

Heme oxygenase-1 accelerates tumor angiogenesis of human pancreatic cancer

Angiogenesis is necessary for the continued growth of solid tumors, invasion and metastasis. Several studies clearly showed that heme oxygenase-1 (HO-1) plays an important role in angiogenesis. In this study, we used the vital microscope system, transparent skinfold model, lung colonization model and transduced pancreatic cancer cell line (Panc-1)/human heme oxygenase-1 (hHO-1) cells, to precisely analyze, for the first time, the effect of hHO-1 gene on tumor growth, angiogenesis and metastasis. Our results revealed that HO-1 stimulates angiogenesis of pancreatic carcinoma in severe combined immune deficient mice. Overexpression of human hHO-1 after its retroviral transfer into Panc-1 cells did not interfere with tumor growth in vitro. While in vivo the development of tumors was accelerated upon transfection with hHO-1. On the other hand, inhibition of heme oxygenase (HO) activity by stannous mesoporphyrin was able transiently to delay tumor growth in a dose dependent manner. Tumor angiogenesis was markedly increased in Panc-1/hHO-1 compared to mock transfected and wild type. Lectin staining and Ki-67 proliferation index confirmed these results. In addition hHO-1 stimulated in vitro tumor angiogenesis and increased endothelial cell survival. In a lung colonization model, overexpression of hHO-1 increased the occurrence of metastasis, while inhibition of HO activity by stannous mesoporphyrin completely inhibited the occurrence of metastasis. In conclusion, overexpression of HO-1 genes potentiates pancreatic cancer aggressiveness, by increasing tumor growth, angiogenesis and metastasis and that the inhibition of the HO system may be of useful benefit for the future treatment of the disease.     

Tumor necrosis factor-related apoptosis-inducing ligand induces neuronal death in a murine model of HIV central nervous system infection

HIV-1 infection in the brain induces neuronal apoptosis leading to HIV-associated dementia. To explore the underlying mechanism, we developed a murine model by using human peripheral blood mononuclear cell (PBMC)-transplanted nonobese diabetic (NOD)-severe combined immunodeficiency (SCID) (hu-PBMC-NOD-SCID) mice. Administration of lipopolysaccharide (LPS) to HIV-1-infected hu-PBMC-NOD-SCID mice induced infiltration of HIV-1-infected human cells into the perivascular region of the brain and neuronal apoptosis was found in macrophage (M)-tropic but not T cell (T)-tropic HIV-1-infected brains. The apoptotic neurons were frequently colocalized with the HIV-1-infected macrophages that expressed tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL). Administration of a neutralizing antibody against human TRAIL but not human TNF-alpha or Fas ligand (FasL) blocked the neuronal apoptosis in the HIV-1-infected brain. These results strongly suggest a critical contribution of TRAIL expressed on HIV-1-infected macrophages to neuronal apoptosis.     

Age has no effect on de novo constitutional t(11;22) translocation frequency in sperm

We analyzed de novo constitutional t(11;22) translocation frequency in sperm derived from normal healthy males as a function of the age of the sperm donors (from 25 to 51). Translocation-specific polymerase chain reaction demonstrated no age-dependent increment in the frequency of the rearrangements.     

An Autopsy Case of Fulminant,Suppurative Bacterial Myocarditis Caused by Group B Streptococcus

A 61-year-old woman was admitted to our hospital with a fever, nausea, diarrhea, and back pain. Her condition rapidly deteriorated, and she was transferred to the intensive-care unit for mechanical circulatory support and antibiotics, but she died 40 hours after admission. Autopsy findings showed necrotic and suppurative myocardial changes due to group B Streptococcus (GBS). To date, only one case of bacterial myocarditis caused by GBS has been reported. We herein report a case of GBS myocarditis, the etiology of which is poorly understood due to the limited number of cases. Bacterial myocarditis should be considered in patients with sepsis and myocardial dysfunction.     

Suppressing effects of daily oral supplementation of beta-glucan extracted from Agaricus blazei Murill on spontaneous and peritoneal disseminated metastasis in mouse model

Purpose: The Basidiomycete fungus Agaricus blazei Murill has traditionally been used as a health food for the prevention of cancer. Methods: We examined whether beta-(1–6)-D-glucan extracted from A. blazei is a potential anticancer agent in an in vitro and in vivo animal model. Results: Here we show that (1) beta-glucan had cytotoxic effect against human ovarian cancer HRA cells, but not against murine Lewis lung cancer 3LL cells, in vitro; (2) beta-glucan promotes p38 MAPK activity for suppressing HRA cell proliferation and amplifying the apoptosis cascade; (3) beta-glucan stimulates translocation of the proapoptotic protein, Bax, from the cytosol to mitochondria, cytochrome c release, and subsequent caspase-9 activation; (4) treatment with SB203580, a p38 MAPK-specific inhibitor, suppresses beta-glucan-induced effects, indicating that activation of p38 MAPK is involved in the suppression of cell proliferation and mitochondrial activation-mediated cell death pathway; (5) in mice, oral supplementation with beta-glucan reduces pulmonary metastasis of 3LL cells and peritoneal disseminated metastasis of HRA cells and inhibits the growth of these metastatic tumors in lung or peritoneal cavity, in part, by suppressing uPA expression; and (6) in an in vivo experimental metastasis assay, however, the oral supplementation with beta-glucan after i.v. tumor cell inoculation did not reduce the number of lung tumor colonies. Conclusion: Treatment with beta-glucan may be beneficial for cancer patients with or at risk for metastasis. The beta-glucan-dependent signaling pathways are critical for our understanding of anticancer events and development of cancer therapeutic agents.